<template>
  <div>
    <h1>
        BaseC.vue-{{ props.MSG }}
        <button @click="changeMsg">打印message</button>
    </h1>
  </div>
   
</template>

<script setup>
import { defineProps,defineEmits } from 'vue';
const props = defineProps({
  MSG: {
     type: String, 
     default: 'hello,world'
     } 
})
const emit = defineEmits(['changeTitle'])
const changeMsg=()=>{
    emit('changeTitle','hello')
}

</script>

<style>

</style>